Electrophilic Trifluoromethylation of Dimetallofullerene Anions en Route to Air-Stable Single-Molecule Magnets with High Blocking Temperature of Magnetization

2021 ◽  
Author(s):  
Yaofeng Wang ◽  
Georgios Velkos ◽  
Noel Jens Israel ◽  
Marco Rosenkranz ◽  
Bernd Büchner ◽  
...  
Keyword(s):  
Single Molecule ◽  
Blocking Temperature ◽  
Single Molecule Magnets

Correlating Blocking Temperatures in Single Molecule Magnets with Raman Relaxation

2018 ◽  
Author(s):  
Marcus J. Giansiracusa ◽  
Andreas Kostopoulos ◽  
George F. S. Whitehead ◽  
David Collison ◽  
Floriana Tuna ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Single Molecule ◽  
Energy Barrier ◽  
Thermal Relaxation ◽  
Relaxation Mechanism ◽  
Blocking Temperature ◽  
Single Molecule Magnets ◽  
Single Molecule Magnet ◽  
Key Parameter

We report a six coordinate DyIII single-molecule magnet<br>(SMM) with an energy barrier of 1110 K for thermal relaxation of<br>magnetization. The sample shows no retention of magnetization<br>even at 2 K and this led us to find a good correlation between the<br>blocking temperature and the Raman relaxation regime for SMMs.<br>The key parameter is the relaxation time (𝜏<sub>switch</sub>) at the point where<br>the Raman relaxation mechanism becomes more important than<br>Orbach.

High performance single-molecule magnets, Orbach or Raman relaxation suppression?

2020 ◽  
Vol 7 (13) ◽  
pp. 2478-2486 ◽  
Author(s):  
Alejandro Castro-Alvarez ◽  
Yolimar Gil ◽  
Leonel Llanos ◽  
Daniel Aravena
Keyword(s):  
Ab Initio ◽  
Single Molecule ◽  
High Performance ◽  
Blocking Temperature ◽  
Single Molecule Magnets

Relaxation mechanisms limiting the blocking temperature for high-performance single molecule magnets (SMMs) are investigated. Best SMMs are limited by the exponential regime. Current ab initio methods can yield accurate estimations for this limit.

scholarly journals Dysprosiacarboranes: A New Type of Organometallic Single-Molecule Magnets

2019 ◽  
Author(s):  
Peng-Bo Jin ◽  
Yuan-Qi Zhai ◽  
Ke-Xin Yu ◽  
Richard E. P. Winpenny ◽  
Yan-Zhen Zheng
Keyword(s):  
Single Molecule ◽  
Energy Barrier ◽  
High Performance ◽  
Blocking Temperature ◽  
Effective Energy ◽  
Single Molecule Magnets ◽  
Linear Complex ◽  
Substitution Pattern ◽  
New Type

Dicarbollide ion, nido-C<sub>2</sub>B<sub>9</sub>H<sub>11</sub><sup>2-</sup> is isoelectronic with cyclopentadienyl. Here we make dysprosiacarboranes, namely [(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>Ln(THF)<sub>2</sub>][Na(THF)<sub>5</sub>] (Ln = Dy, <b>1Dy</b>) and [(THF)<sub>3</sub>(μ-H)<sub>3</sub>Li]<sub>2</sub>[{η<sup>5</sup>-C<sub>6</sub>H<sub>4</sub>(CH<sub>2</sub>)<sub>2</sub>C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>}Dy{η<sup>2</sup>:η<sup>5</sup>-C<sub>6</sub>H<sub>4</sub>(CH<sub>2</sub>)<sub>2</sub>C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>}<sub>2</sub>Li] <b>3</b> and show that dicarbollide ligands impose strong magnetic axiality on the central Dy(III) ion. The effective energy barrier (Ueff) for loss of magnetisation can be varied by the substitution pattern on the dicarbollide. This is demonstrated by comparing complexes of nido-C<sub>2</sub>B<sub>9</sub>H<sub>11</sub><sup>2-</sup> and nido-[o-xylylene-C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>]<sup>2-</sup> which show Ueff of 430(5) K and 804(7) K, respectively. The blocking temperature defined by the open hysteresis temperature of 3 reaches 6.8 K. Moreover, the linear complex [Dy(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>]<sup>-</sup> is predicted to have comparable SMM properties with linear [Dy(CpMe<sub>3</sub>)<sub>2</sub>]<sup>+</sup> complex. As such, carboranyl ligands and its derivatives may open a new type of organometallic ligands for high-performance SMM design. <br>

Correlating Blocking Temperatures in Single Molecule Magnets with Raman Relaxation

2018 ◽  
Author(s):  
Marcus J. Giansiracusa ◽  
Andreas Kostopoulos ◽  
George F. S. Whitehead ◽  
David Collison ◽  
Floriana Tuna ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Single Molecule ◽  
Energy Barrier ◽  
Thermal Relaxation ◽  
Relaxation Mechanism ◽  
Blocking Temperature ◽  
Single Molecule Magnets ◽  
Single Molecule Magnet ◽  
Key Parameter

We report a six coordinate DyIII single-molecule magnet<br>(SMM) with an energy barrier of 1110 K for thermal relaxation of<br>magnetization. The sample shows no retention of magnetization<br>even at 2 K and this led us to find a good correlation between the<br>blocking temperature and the Raman relaxation regime for SMMs.<br>The key parameter is the relaxation time (𝜏<sub>switch</sub>) at the point where<br>the Raman relaxation mechanism becomes more important than<br>Orbach.

Metallacryptate Single-Molecule Magnets:  Effect of Lower Molecular Symmetry on Blocking Temperature

2005 ◽  
Vol 127 (37) ◽  
pp. 12862-12872 ◽  
Author(s):  
Curtis M. Zaleski ◽  
Ezra C. Depperman ◽  
Catherine Dendrinou-Samara ◽  
Maria Alexiou ◽  
Jeff W. Kampf ◽  
...  
Keyword(s):  
Single Molecule ◽  
Blocking Temperature ◽  
Molecular Symmetry ◽  
Single Molecule Magnets

Enhancing the magnetic blocking temperature and magnetic coercivity of {CrIII2LnIII2} single-molecule magnets via bridging ligand modification

2016 ◽  
Vol 52 (73) ◽  
pp. 10976-10979 ◽  
Author(s):  
Stuart K. Langley ◽  
Daniel P. Wielechowski ◽  
Boujemaa Moubaraki ◽  
Keith S. Murray
Keyword(s):  
Relaxation Time ◽  
Single Molecule ◽  
Magnetic Relaxation ◽  
Magnetic Hysteresis ◽  
Blocking Temperature ◽  
Single Molecule Magnets ◽  
Ligand Modification ◽  
Bridging Ligand

Replacing bridging benzoate ligands with 2-chloro-4,5-fluorobenzoate in a family of {CrIII2LnIII2} (Ln = Tb, Dy and Ho) single-molecule magnets results in significant improvements in magnetic relaxation time, magnetic hysteresis blocking temperature and magnetic coercivity.

Single Molecular Magnet - Gold Nanoparticle Composites

2009 ◽  
Vol 1198 ◽  
Author(s):  
Gopalan Balaji ◽  
Gudrun Bovenkamp ◽  
Vadim Palshin ◽  
Challa Kumar
Keyword(s):  
Gold Nanoparticle ◽  
Data Storage ◽  
Single Molecule ◽  
Composite Structures ◽  
Blocking Temperature ◽  
Molecular Magnet ◽  
Transition Elements ◽  
Single Molecule Magnets ◽  
Potential Applications ◽  
Ultrahigh Density

AbstractThe past decade has witnessed a great interest in single molecule magnets (SMM) especially those based on manganese such as Mn12-acetate due to their potential applications in ultrahigh density data storage and quantum computing devices. The focus so far has been in finding different derivatives of Mn or other complexes based on transition elements in order to raise the blocking temperature of single-molecule magnets (SMMs). Herein we propose a fundamentally new approach of generating new category of SMMs through formation of composite structures by binding SMMs on to nanoparticles. In this report, we present the synthesis and characterization of single molecular magnet - gold nanoparticle composite- Mn12-cysteinate functionalized gold nanoparticles.

scholarly journals Magnetic hysteresis up to 80 kelvin in a dysprosium metallocene single-molecule magnet

Science ◽  
2018 ◽  
Vol 362 (6421) ◽  
pp. 1400-1403 ◽  
Author(s):  
Fu-Sheng Guo ◽  
Benjamin M. Day ◽  
Yan-Cong Chen ◽  
Ming-Liang Tong ◽  
Akseli Mansikkamäki ◽  
...  
Keyword(s):  
Single Molecule ◽  
Magnetic Hysteresis ◽  
Information Storage ◽  
Blocking Temperature ◽  
Wave Number ◽  
Magnetic Memory ◽  
Single Molecule Magnets ◽  
Single Molecule Magnet ◽  
Chemical Strategy ◽  
Lower Size

Single-molecule magnets (SMMs) containing only one metal center may represent the lower size limit for molecule-based magnetic information storage materials. Their current drawback is that all SMMs require liquid-helium cooling to show magnetic memory effects. We now report a chemical strategy to access the dysprosium metallocene cation [(CpiPr5)Dy(Cp*)]+ (CpiPr5, penta-iso-propylcyclopentadienyl; Cp*, pentamethylcyclopentadienyl), which displays magnetic hysteresis above liquid-nitrogen temperatures. An effective energy barrier to reversal of the magnetization of Ueff = 1541 wave number is also measured. The magnetic blocking temperature of TB = 80 kelvin for this cation overcomes an essential barrier toward the development of nanomagnet devices that function at practical temperatures.

scholarly journals Dysprosiacarboranes: A New Type of Organometallic Single-Molecule Magnets

2019 ◽  
Author(s):  
Peng-Bo Jin ◽  
Yuan-Qi Zhai ◽  
Ke-Xin Yu ◽  
Richard E. P. Winpenny ◽  
Yan-Zhen Zheng
Keyword(s):  
Single Molecule ◽  
Energy Barrier ◽  
High Performance ◽  
Blocking Temperature ◽  
Effective Energy ◽  
Single Molecule Magnets ◽  
Linear Complex ◽  
Substitution Pattern ◽  
New Type

Dicarbollide ion, nido-C<sub>2</sub>B<sub>9</sub>H<sub>11</sub><sup>2-</sup> is isoelectronic with cyclopentadienyl. Here we make dysprosiacarboranes, namely [(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>Ln(THF)<sub>2</sub>][Na(THF)<sub>5</sub>] (Ln = Dy, <b>1Dy</b>) and [(THF)<sub>3</sub>(μ-H)<sub>3</sub>Li]<sub>2</sub>[{η<sup>5</sup>-C<sub>6</sub>H<sub>4</sub>(CH<sub>2</sub>)<sub>2</sub>C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>}Dy{η<sup>2</sup>:η<sup>5</sup>-C<sub>6</sub>H<sub>4</sub>(CH<sub>2</sub>)<sub>2</sub>C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>}<sub>2</sub>Li] <b>3</b> and show that dicarbollide ligands impose strong magnetic axiality on the central Dy(III) ion. The effective energy barrier (Ueff) for loss of magnetisation can be varied by the substitution pattern on the dicarbollide. This is demonstrated by comparing complexes of nido-C<sub>2</sub>B<sub>9</sub>H<sub>11</sub><sup>2-</sup> and nido-[o-xylylene-C<sub>2</sub>B<sub>9</sub>H<sub>9</sub>]<sup>2-</sup> which show Ueff of 430(5) K and 804(7) K, respectively. The blocking temperature defined by the open hysteresis temperature of 3 reaches 6.8 K. Moreover, the linear complex [Dy(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>]<sup>-</sup> is predicted to have comparable SMM properties with linear [Dy(CpMe<sub>3</sub>)<sub>2</sub>]<sup>+</sup> complex. As such, carboranyl ligands and its derivatives may open a new type of organometallic ligands for high-performance SMM design. <br>

Enhancing the Blocking Temperature in Single-Molecule Magnets by Incorporating 3d-5d Exchange Interactions

2010 ◽  
Vol 16 (45) ◽  
pp. 13458-13464 ◽  
Author(s):  
Kasper S. Pedersen ◽  
Magnus Schau-Magnussen ◽  
Jesper Bendix ◽  
Høgni Weihe ◽  
Andrei V. Palii ◽  
...  
Keyword(s):  
Single Molecule ◽  
Exchange Interactions ◽  
Blocking Temperature ◽  
Single Molecule Magnets
Sign in / Sign up

Export Citation Format

Share Document